Bite gauge



J. E. KOVATS J1me 25, 1940.

BITE GAUGE Filed April 18, 1938 7; 0 5 4 M M M724 Patented June 25, 1949Midi-TED STATES BITE GAUGE Joseph E. Kovats, Chicago, Ill. ApplicationApril 18, 1938, Serial No. 202,635

3 Claims.

Ihis invention relates to a novel and. original bite gauge to determinethe central axis of the hinge between the upper and lower jaw bones ofman for dental or surgical purposes. An im- 5 portant and wide field forits use is found in dentistry in the making of dentures, when it isrequired to determine the normal position of the jaws in a natural biteof the patient, without lateral or frontal displacement.

The invention may also find wide use for surgical purposes.

It has long been known that the patient cannot definitely determine hisnatural bite, when a dentist is making a simple denture or a fulldenture. The object of the invention is to provide a bite gauge which,with the co-operation of the patient opening and closing his jaws at thedirection of the dentist, will indicate by a suitable signal when saidnormal bite has oo- 20 curred. With such normal bite the final denturemay be made.

Other objects and advantages of the invention will more fully appearfrom the following specification:

' application is a continuation in part of my ccpending application,Serial No. 113,935,

filed December 2, 1936.

In the drawing:

Fig. l is a perspective view of one embodiment of the invention, withsome parts broken away tomore clearly illustrate the internalconstruction;

Fig. 2 is plan view of a cover plate referred to more particularlylater.

Fig. 3 is a cross-section of the device in a plane indicated by the line3--3 of Fig. 1.

My invention depends for its operation upon the known fact that when thejaws are closed to a bite, with frontal or lateral displacement, littleor no enlargement or bulging of the jaw muscles occurs. But when thejaws swing together upon their normal central hinge axis and are broughttogether in their natural, intended normal bite position, a rigidexpansion of all the muscles involved in mastication occurs.

Referring now to that embodiment of the invention illustrated in thedrawing: l0, l indicate opposed pressure-gauges or pressure-reactingplungers which are designed for engagement 50 with opposite sides of theface in the neighborhood of the hinge axis of the jaws. Said plungersare spring-controlled and are adapted for yielding engagement underpressure against the face, being each mounted for longitudinal movement55 in an opening 56* in an arm H, which carries it.

iii

Any suitable spring mounting for the plunger in may be used. I

I2 indicates a cylindrical fitting having a base H by means of which itis attached to the associated arm H. The plunger I0 is mounted for 5longitudinal movement in said fitting and is normally retained againstmovement by means of a helical spring !3 surrounding it and fixed toitat one end, said spring being seated at its other end against the base12 of the fitting. Obviously, by means of the arms H, II, the opposedends of the plungers I0 may be engaged against opposite sides of theface and brought by the arms H, H into yielding engagement therewith. Byproper adjustment of the pressure the plungers may be made to lightlyindent the skin and approach indirect engagement with the greaterresistant jaw muscular structure therebelow. Then upon expansion of saidmuscular structure, the resistant action of the springs I2 2 will beovercome and the 'plungers l0 will be snapped-further apart in theirmounting openings lll and the'arms H.

Since the movement of the plungers I0 is but a small fraction of acentimeter, their movement, 26 whether .to indirectly engage the jawmuscles or their further movement apart upon expansion of the jawmuscles, is too smallfor ready observation. I, therefore, prefer toemploy an amplifying device for indicating such movement. 30

In the drawing, I3 indicates a lever needle pivotally mounted on a pinl3 in a casing M inthe plane of the arm II and plunger I0. Said needlehas a short arm engaging said plunger and a much longer arm associatedwith a scale I5 remote from the plunger I 0. A spring l3 holds theshorter arm of the needle in engagement with the plunger. Anintermediate point w in the scale corresponds to thejpos'ition of theplunger when the plunger has been brought 40 to a position depressingthe skin of the face and approaching indirect contact with the moreresistant jaw muscles. Thereafter when a proper bite is given, theneedle will snap to its limit of movement indicated on the, scale at,l5".

The arms H are pivotally connected at their ends remote from theplungers Hi to a plate I6. Said plate has an arcuate rib I! and ahorizontal rib l8 arising from its face and spaced apart at their endsto provide openings l9, [9 through which the ends of the arms H, IIextend. Each arm is pivotally connected to the plate l6 by a pin 20 at apoint short of its end. 2| indicates a block slidable upon the plate I6.22 indicates a screw threaded through said block and through the arcuaterib ll beyond which it has a knurled head 23 fixed to it. The screwitself is locked against endwise movement by means of a pin 24 mountedin the rib l1 and engaging a groove in the screw. Obviously rotation ofthe screw 22 will cause the block 2! to travel in one direction or theother between the rib l8 and the rib H. The block 2| is provided withlateral flanges 25, each provided with upwardly inclined slots 25*. Eacharm II is bifurcated at its end beyond its pivot pin 2!] and embraces aflange 25 of the block 2! and is provided with pivotal relationtherewith by means of a pin 26. The plate Hi shown in Fig. 2 is adaptedto be attached to the ribs ii and I8, thus providing a closed casing inwhich the parts above described are held.

By the foregoing construction, it is obvious that micrometerlikeadjustment of the arms I l l I towards or away from each other may bemade by turning the screw 22 in one or the other direction.

The arms H, II are preferably made long enough so that when the plungersID are brought to the desired position on the sides of the face, saidarms will depend below the chin of the patie'nt, so that the operatormay steady his hold on the apparatus when using it by resting his handagainst the chest of the patient.

The operation of the device is as follows: By proper adjustment of thescrew 22, the plungers l0, H] are applied to the sides of the face inthe neighborhood of the central hinge axis of the jaws. The plungers arethen brought lightly into engagement with the skin, the adjustment beingcontinued until the skin is slightly indented and the ends of theplungers have come to indirect contact with the jaw muscles. This pointmay be predetermined and indicated on the scale l5 as heretofore pointedout. Thus in the case illustrated, the adjustment is continued until theneedle of both arms comes to comparative rest at the point i5 on thescale.

The patient is then required to open and close his jaws several times tomake a proper bite. This, however, will have no efiect on the plungersas long as there is front or lateral displacement of the jaws. When,however, a bite without such displacement is produced, the jaw muscleswill immediately expand and force the plungers I0 farther apart, causingthe needle l3 to snap from its position at the point l5 to point l5against the arm II. This indicates to the operator that the bite is thenormal bite of the patient.

The advantages of the invention will be manifest to those familiar withthe art.

While in describing one embodiment of my invention I have referred tomany details of construction and arrangement of parts and haveillustrated but one form of indicating device, it will be understoodthat said details and arrangement may be modified in several ways, andthat the invention is not limited thereto except as may be pointed outin the appended claims.

I claim as the invention:

1. A bite gauge comprising a base, spaced arms each pivotally connectedat one end to said base and being free at the other end, means mountedon said base in operative engagement with said arms for providingmicrometer adjustments of the space between the free ends of said arms,spring controlled opposed plungers carried at the free end of said armsand a visual indicating device for each arm adapted to indicate themovement of said plungers.

2. A bite gauge comprising a base, spaced arms each pivotally connectedat one end to said base and being free at the other end, means mountedon said base in operative engagement with said arms for providingmicrometer adjustments of the space between the free ends of said arms,spring controlled opposed plungers carried at the free ends of said armsand a visual indicating device for each arm adapted to indicate apredetermined initial and a final movement of its associated plunger.

3. A bite gauge comprising a base, spaced arms each pivotally connectedat one end to said base and being free at the other end, means mountedon said base in operative engagement with said arms for providingmicrometer adjustments of the space between the free ends of said arms,spring controlled opposed plungers carried at the free ends of saidarms, an amplifying device for registering the movement of saidplungers, and

a visual indicating device associated with said amplifying deviceadapted to indicate a predetermined initial and a final movement of saidplungers.

JOSEPH E. KOVATS.

